In U.S. patent application Ser. No. 10/002,567, entitled “Active Adapter Chip for Use in a Flash Card Reader”, filed Nov. 1, 2001, and assigned to the assignee of the present application, a universal active adapter chip is disclosed that can be used to construct a flash media system or various active flash media adapters using the CompactFlash card or PCMCIA (PC Card) form factor. A standard reader that reads CompactFlash cards or PC cards can then read any of the other flash-memory cards that plug into the CompactFlash or PC Card adapter. The adapters come with a conversion chip that makes each of the flash media work just like a CompactFlash or PC Card media, as applicable.
FIG. 1 shows a multi-standard card reader system 142. In the field of multi-standard adapters, multi-memory media adapter 140 may be an active adapter or, alternatively, may be a passive adapter. Reader 142 can adapt on the host side to either CompactFlash card 149, PCMCIA card 153, or IDE card 151. On the media side, the reader can adapt to a MultiMediaCard 141, or a Secure Digital card 143, which have the same form factor but slightly different pin-out; a SmartMedia card 145, which has a different pin-out; or a Memory Stick 147. In general, the reader 142 can adapt to any generic flash media 146 that has a similar or smaller form factor.
It is possible to place the connector such that all the media sit in one opening. FIG. 2 is a cutaway side view of a PCMCIA adapter card 200 of the type that is available as a standard commercial product today. FIG. 2 illustrates several drawbacks in the typical configuration of a PCMCIA adapter. Adapter 200 includes two PCBs, namely PCB 210 and PCB 220. The two PCBs are separated by a mounting frame (typically plastic), not shown. The mounting frame acts as a spacer between PCB 210 and PCB 220, which holds the two PCBs together at a specified distance and functions in other capacities as described below. The space between the two PCBs creates the opening (port) 211 into which the flash media cards are inserted. PCB 230 is straddle-mounted between PCB 210 and PCB 220. PCB 230 contains the active components including controller chip 231 that perform handshaking and data transfer. PCB 230 is connected to a PCMCIA connector 240. PCB 230 is mounted between PCB 210 and PCB 220 with interconnects 212. PCB 210 has two sets of floating contact pins, contact pin set 214 includes nine contact pins and contact pin set 215 includes ten contact pins, which provide interfaces for MMC/SD and MemoryStick flash media respectively. PCB 220 has two sets of floating contact pins 224 and 225, each including 11 pins, which together provide the interface for SmartMedia flash media.
The mounting frame that holds PCB 210 and 220 together is configured such that each type of flash media is inserted in a particular location within the connector. In FIG. 2, opening 211 is a simplified view. Typically, the opening is stepped with different widths and heights in different locations that index the flash media cards into specific locations upon insertion. This allows each flash medium to be properly aligned with the corresponding contact pin set(s). Additionally, stops are typically provided to stop the insertion at the correct depth, again, to guarantee connection to the right contact pin set.
This typical approach has several serious drawbacks.
Manufacturing
The straddle-mount configured flash media adapter is very expensive to manufacture for several reasons. Often such devices require manual labor for manufacturing and testing, or the use of very expensive soldering robots, instead of standard production techniques. A further problem is the additive effect of manufacturing tolerances, such as primary connector (i.e., PCMCIA) to PCB, to straddle mount connector to secondary PCB to contacts on PCB, resulting in as many as two, three, or in some cases even four tolerances adding up, which makes requirements for tolerances either absurdly expensive, or causes a big yield problem in manufacturing. Additionally, PCB 230 must be thin enough so that it can be mounted between PCB 210 and PCB 220 in the space allocated for the insertion of the various flash media. That is, PCB 230, together with the interconnects 212 that mount it between PCB 210 and PCB 220 must be no larger than opening 211. The manufacture of thin PCBs to accommodate this design point adds to the expense and complexity of manufacturing the flash media adapter.
Contact Pins
The floating contact pins are subject to damage and deterioration. The various flash media cards have different thickness, and even the same flash media may have different thickness if produced by different manufacturers. The flash media cards exert pressure upon the floating contact pins, which eventually causes their resiliency to be reduced. When subsequently, a thinner flash media card is inserted into the flash media adapter, the corresponding contact pins may not make connection with the flash media card. Additionally if a flash media card is inserted incorrectly (e.g., upside down), removal of the flash media card may damage the contact pins.
Interface
Some devices don't have the 68-pin PCMCIA interface. For example, some recent notebook computer models only have the electrically equivalent 50-pin CF interface. Typical adapter cards such as PCMCIA adapter card 200 are incompatible with a 50-pin CF interface.